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Four species of mole crickets (Orthoptera: Gryllotalpidae) are known from the West Indies: Neocurtilla hexadactyla (Perty), Scapteriscus abbreviatus Scudder, S. didactylus (Latreille), and S. imitatus Nickle and Castner. All are adventive (not native). We document their distributions in West Indian islands/countries by use of records from the literature and examination of specimens. Scapteriscus abbreviatus has been suggested to have arrived in, and been transported about the West Indies in ship ballast (immigration). Based on records of arrival in various parts of the West Indies and the species’ inability to fly, this suggestion seems reasonable. Scapteriscus imitatus pparently was released in Puerto Rico as a result of mistaken identification (introduction – arriving with assistance from humans – although inadvertent), and has not expanded its range in the West Indies. Although the principal mode of dispersal for the other two species also has been suggested to be ship ballast, we present an alternative based on flight which would seem at least equally as plausible. We suggest that S. didactylus could have dispersed by flight from South America through the Lesser Antilles; likewise N. hexadactyla probably from the Yucatan Peninsula to Cuba, and from South America northward through the Lesser Antilles, in at least some localities assisted by wind. Our zoogeographical alternative, if correct, means that the natural range expansions of these latter two species began very long ago and without human assistance – they were not introduced recently to the West Indies.

The known range of Oxybleptes meridionalis Smetana (Coleoptera: Staphylinidae) is expanded in Florida, USA, from Indian River and Manatee counties to now include Brevard, Highlands, Orange, Seminole and Volusia. Oxybleptes davisi (Notman) is confi rmed to exist in Florida, with records from Leon, Liberty and Wakulla counties in the Panhandle, and Orange County in central Florida. Lissohypnus texanus Casey is newly reported from Florida. A new species, Lissohypnus fullertoni, is described from Florida. Diochus schaumii Kraatz reverts to this original spelling; its widespread form in Florida is identical to that in the northeastern USA.

One male specimen of Neoxantholinus cristatus Smetana (Coleoptera: Staphylinidae), collected in 1993, is reported from Grand Cayman. The presence of that species brings to 63 the number of species of Staphylinidae reported from the Cayman Islands.

Adults, and in some species larvae, of several members of Belonuchus Nordmann (Coleoptera: Staphylinidae: Staphylininae) and a few related genera seem to be to various degrees consistently associated with flower bracts of the genus Heliconia (Zingiberales: Heliconiaceae). They are predators and eat various dipterous and lepidopterous larvae in that habitat. Adults of at least Belonuchus cephalotes (Sharp) and Odontolinus fasciatus Sharp are able to immerse completely in water to capture larvae and/or pupae of mosquitoes (Culicidae). Adults and larvae of Belonuchus satyrus Erichson, and adults of B. cacao Blackwelder and B. rufipennis (F.) were found in water-filled flower bracts of Heliconia bihai (L.) L. in northern, lowland Venezuela. The bracts also contained mosquito larvae and semiaquatic coleopterous (Chrysomelidae: Hispinae), lepidopterous (Crambidae: Pyraustinae) and dipterous (Syrphidae, Stratiomyidae, Psychodidae, Richardiidae) larvae, and Annelida. In feeding trials, B. satyrus adults and larvae did not feed on hispine larvae or annelids, but did feed on all the lepidopterous and dipterous larvae available to them; adults dragged larvae and pupae of the mosquito genus Toxorhynchites Theobald from shallow water and thus seemed to be the top predators of the food pyramid within bracts. Records are compiled of association of Belonuchus and relatives with Heliconia bracts in the neotropics. We correct the names used for Heliconia spp. by earlier entomological authors working in Venezuela. Their ‘Heliconia caribaea Lamarck’ is H. bihai (L.) L. and their ‘H. aurea Rodríguez’ is H. bihai cv. Aurea.

We document the presence of Larra bicolor Fabricius (Hymenoptera: Crabronidae) in 46 of Florida's 67 counties. The species is represented by two stocks. The first (released in 1981) originated in Pará, Brazil, but was obtained from Puerto Rico, and became established in Broward County in southern Florida. The second (released in 1988) originated in Santa Cruz de la Sierra, Bolivia, and became established in Alachua County in northern Florida. The Bolivian stock, aided by additional satellite releases from Alachua County, is now widely distributed. The species probably occupies all counties in central and northern Florida, but may yet be absent from some southern counties. Introduction was made for classical biological control of invasive mole crickets.

In 1947, 20 species of Staphylinidae were reported from the Cayman Islands as a result of an Oxford University expedition there in 1938 which made extensive use of a light trap. The list is here expanded to 62 species based on collections by R. R. Askew, G. E. Ball, E. A. Dilbert, B. K. Dozier, E. J. Gerberg, P. J. Fitzgerald, M. C. Thomas, and R. H. Turnbow since 1970, all of whom also used light traps except for a collection or two by flight intercept trap.

Published claims in 1887-1903 that the mole cricket Neocurtilla hexadactyla (Perty) occurs in Puerto Rico all seem to be derived from a misidentification made by Agustín Stahl, a medical practitioner and collector of natural history objects, published in 1882. That species does not seem now to occur in Puerto Rico and almost certainly never did. However, the opportunity still exists for it to colonize by wind-assisted flight from islands to the southeast just as we believe did the mole cricket Scapteriscus didactylus (Latreille) as an immigrant. Stahl evidently mistook the latter for the former. According to some subsequent authors, he also stated that it (the mole cricket now believed to be S. didactylus) arrived in the port of Mayagüez in a cargo of guano about 1850 from Peru and thus colonized Puerto Rico. We found no verification for that story, and we doubt it. The first detection of the presence of S. didactylus in Puerto Rico may have been by a French expedition in 1797, but this species may have been present much earlier. Two other species of Scapteriscus were later detected in Puerto Rico. One, S. abbreviatus Scudder, was detected in 1917 and likely arrived as a contaminant of ship ballast some time earlier, perhaps at the port of Mayagüez. The other, S. imitatus Nickle and Castner, was detected about 1940 and seems to have been introduced inadvertently, as a result of mistaken identity. In broad terms, S. didactylus, S. abbreviatus, and S. imitatus are adventive species (meaning they arrived from somewhere else and are not native) in Puerto Rico. The vernacular name changa in Puerto Rico is owned by S. didactylus, which is called West Indian mole cricket in the English-speaking Caribbean. Historical accounts suggest that populations of S. didactylus and of two pest Phyllophaga spp. (Coleoptera: Scarabaeidae) surged after 1876/1877 and declined after 1920. This coincidence suggests that the cause may have been the same. The cause of the rise might conceivably have been introduction of the mongoose Herpestes javanicus (E. Geoffroy St. Hilaire) in 1877 (because it may have destroyed vertebrate predators) and the cause of the decline might conceivably have been introduction of the toad Bufo marinus L. in 1920, because it is a predator of Phyllophaga and Scapteriscus.